Where on the IRS website can I find what is the interest rate on unpaid taxes. I imagine this will be the interest rate charged during an installment agreement, or if you just didn't pay your tax on time; is that so?
Best I could find after a google search is a revenue ruling.
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6621.--Determination of Rate of Interest
From the last line in page 7 it looks to be 5% for Jan. 1, 2009--Mar.
31, 2009. Is that true? What about now?